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A096400
Number of equivalence classes of triangles having equal angles of integral degrees and smallest angle = n.
0
89, 88, 86, 85, 83, 82, 80, 79, 77, 76, 74, 73, 71, 70, 68, 67, 65, 64, 62, 61, 59, 58, 56, 55, 53, 52, 50, 49, 47, 46, 44, 43, 41, 40, 38, 37, 35, 34, 32, 31, 29, 28, 26, 25, 23, 22, 20, 19, 17, 16, 14, 13, 11, 10, 8, 7, 5, 4, 2, 1
OFFSET
1,1
COMMENTS
a(n) mod 3 > 0: a(n) = 90 - A001651(n-1).
FORMULA
a(n) = floor((180 - 3*n)/2) + 1.
EXAMPLE
a(58) = #{(58,58,64),(58,59,63),(58,60,62),(58,61,61)} = 4;
a(59) = #{(59,59,62),(59,60,61)} = 2;
a(60) = #{(60,60,60)} = 1, the last term.
CROSSREFS
Sequence in context: A152160 A075481 A104925 * A074119 A253648 A373915
KEYWORD
nonn,fini,full
AUTHOR
Reinhard Zumkeller, Aug 06 2004
STATUS
approved